1 a Britain : a fine grade of oak imported for woodwork b (1) : a wooden lining of an interior wall usually paneled (2) : a lining of an interior wall irrespective of material *a tile wainscot* c : the lower three or four feet of an interior wall when finished differently from the remainder of the wall (as with wood panels, tile, or marble slabs) 2 : any of various European and American noctuid moths belonging to the genera Leucania and Cirphis that are reddish or yellowish and are streaked or lined with black and white and that in the larval stage are army worms.